1. Field of the Invention
The present invention generally relates to window coverings and treatments that include a plurality of individual cells that are variably adjustable between a collapsed position and an expanded position. More specifically, the present invention relates to the cells of a multi-cell window covering and a method for manufacturing the cells of a multi-cell window covering.
2. Description of the Related Art
Partly in response to the limitations inherent in traditional window coverings like venetian blinds, fresh window coverings and treatments, such as multi-cellular shades, were developed and welcomed by consumers. In the broad sense, a cellular shade is a window covering having a plurality of cells arranged adjacent to one another. The adjacent cells are bonded at their edges to form a complete sheet for the window covering. These multi-cellular shades provide significant insulating value, uniform light diffusion and a desirable aesthetic presentation, but they typically have no view-through capability. Unlike traditional venetian blinds, which provide easy modulatable view-through and light control by simply adjusting the orientation of the horizontally disposed slats or vanes, traditional multi-cellular shades are not capable of separating the plurality of cells, thus preventing a view-through option. Therefore, in order for a person to see through a window that is outfitted with a traditional multi-cellular shade, it is necessary to collectively raise and gather the plurality of cells, i.e., raise the entire window covering. However, raising the whole cellular window shade is laborious and time consuming.
In light of the advantages of venetian blind and multi-cellular window shades, a hybrid window covering was developed that provides the characteristics of both a venetian blind and a multi-cellular window covering. This hybrid window covering includes a plurality of cells arranged parallel to one another. Each cell has at least one side, and a joint that unites adjacent sides of each cell. The adjacent sides are pivotable about the joint such that each cell is variably adjustable between a collapsed position and an expanded position. By collapsing and expanding the cells, the window covering can achieve adjustable light-control, modulatable view-through, light diffusion, and excellent insulation value, all in an aesthetically pleasing design.
Included in this hybrid window covering is a means for variably adjusting the cells between the collapsed position, where adjacent cells are separated, and the expanded position, where adjacent cells contact one another. The adjustment means typically includes a pair of cords that engage and actuate the cells between the collapsed and expanded positions. Due to the structure of the cells, the relative position of the cords in each pair is not fore-and-aft (i.e., perpendicular to the plane of the window covering), as in a conventional venetian blind, but rather is parallel to the plane of the window covering for central, balanced lifting and lowering of the upper and lower portions of each cell. A series of beads or other suitable attachment elements are secured to the cords and are engaged with one or more surfaces of the cells during manufacture.
FIG. 1 of the drawings illustrates an exemplary window treatment employing the cell and cord arrangement described above. Note that in location xe2x80x9cA,xe2x80x9d the upper surface of the cell includes a relatively small bead-engaging aperture aligned vertically with a larger cord clearance aperture on the lower surface of the cell. Alternatively, at location xe2x80x9cB,xe2x80x9d the relatively small bead-engaging aperture is located on the lower surface of the cell and the larger cord-clearance aperture is located on the upper surface of the cell. Manufacturing alternating apertures on the upper and lower surfaces of a pre-manufactured, multi-surface cell is generally impractical, as it would require a separate manufacturing operation on the upper and lower surfaces of the cell. The difference in aperture size alone, regardless of the orientation between dissimilar apertures, renders their formation difficult with conventional punch tooling. In such a manufacturing operation, custom tooling is required to make a two-stage cut in the cell. Additionally, the scrap material from the punched upper aperture is likely to be retained in the cell, having no sufficiently sized hole in the lower surface of the cell to drop through.
A cell and method of manufacturing a cell for a multi-cell window covering is disclosed. The method begins with the step of providing a flexible material defined as an elongated member having axial and transverse directions. A portion of the flexible material is then stiffened to create at least one axially extending flexible junction. At least one control engagement formation and at least one control clearance formation are then created in axially extending sections of the stiffened flexible material that will become an upper portion and a lower portion of the cell. The flexible material is then folded to create a closed element and the flexible material is secured to itself to maintain the shape of the closed element.
The method of the present invention enables the manufacture of expandable and collapsible cells for a window covering, using common raw materials. The proposed method uses relatively inexpensive tooling to produce cells having distinct features in the upper and lower surfaces of the cells. The ability to create distinct features in the top and bottom surfaces of the cells enables the use of cords that selectively engage either the upper or lower portions of the cells at predetermined locations.
Various additional aspects of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiments, when read in light of the accompanying drawings.